Migrants and refugees from Pakistan shout slogans as they demonstrate in front of Macedonian policemen while waiting to cross the Greek-Macedonian border near Gevgelija on November 23, 2015. (Robert Atanasovski/AFP/Getty Images)

Authorities in Macedonia have begun turning away migrants who are unable to prove that they are fleeing war in Syria, Afghanistan or Iraq, leaving thousands of people stranded at the border with Greece.

Some of the migrants have protested daily since the stricter screenings were announced last week, at times preventing others from crossing into Macedonia.

In one of the largest protests, riot police formed a barricade Sunday before a crowd of about 100 young men from Morocco and Iran who chanted, “We want to live!” and “We are not terrorists!” while holding signs begging for help.

Caught on a rocky bank nearby, other migrants anxiously watched.

“My family sold everything for me to come here,” said Muhammad Askito, 23, who is traveling with his wife, Ilham, 21, both from Morocco. “My mother was crying as I left, but she told me, ‘Go. There is no future here.’ ”

A migrant with his mouth sewn shut in protest of not being able to continue his journey, at the Greek-Macedonian border near Gevgelija on November 23, 2015. (Robert Atanasovski/AFP/Getty Images)

As security concerns spread throughout Europe in the wake of the deadly Paris attacks, Croatia, Slovenia and Serbia announced similar restrictions last week. Still, the flow of people using the Balkans route to reach Western Europe has shown no signs of slowing down, contributing to a bottleneck of migrants in the southern part of the region.

Without its stricter screening process at the Greek border, Macedonia apparently feared being forced to take in all of the migrants crossing there as well as those turned away at the Serbian border.

Macedonia’s Ministry of Foreign Affairs said in a statement that the “humane treatment” of war refugees was foremost in its efforts but that “we must secure control of our borders.” That has necessitated, it said, a process to differentiate between economic migrants and those escaping war. The statement left unclear how the process would improve security.

Migrants fleeing economic hardship are a minority among the migrants arriving in Europe: According to the United Nations, of the more than 700,000 migrants who have arrived in Greece this year, 62 percent are Syrian, 23 percent are from Afghanistan and 7 percent are Iraqi, meaning 9 percent are from less war-battered nations.

But some of the people backed up at the Macedonian border insist that even though they are not fleeing war, their reasons for leaving home are still a matter of life or death.

Hamid Laj, 23, a musician in Iran, pulled a small gold cross from under his shirt when asked why he had fled. He said he had converted to Christianity. “If I go back to Iran, they will kill me,” he said, drawing his thumb across his neck.

Like many here, Laj was aware of tightened security across Europe since the attacks in Paris. “We are so sad for Paris,” he said. “But we are not terrorists. We just don’t have freedom. What is the difference between Iranian people and Syrian people?”

He then rolled up the sleeves of his American flag T-shirt, displaying scars crisscrossing his arms. “This is what happens in Iran. We cannot go back,” Laj said. “And we cannot go on. Where do we go?”

Laj was sitting about 100 feet behind the border fence in one of several large white tents set up by Doctors Without Borders and the U.N. High Commissioner for Refugees to house about 1,500 migrants here who have been denied entry into Macedonia and are stuck in limbo.

As aid workers began to distribute food, a long line formed, stretching back almost a mile.

Standing in the line was Betty Akol, 37, from South Sudan, with her 7-year-old daughter, who held a large orange balloon.

“You would not believe the cruelty that is going on in our country,” she said, describing the ongoing civil war in South ­Sudan. “So many people lost their lives.”

A single mother, Akol struggled to care for her three children.

“When I left Sudan, I realized I could only take one,” she said. She said she took her daughter to Turkey and left her other two children with her parents, who fled to Uganda. “I don’t know what is happening to my babies,” she added.

The UNHCR has condemned the decision by authorities in not only in Macedonia but also in Slovenia, Croatia and Serbia, which have all started rejecting migrants who have not come from war zones.

“This will bring a lot of suffering to the people trying to get through,” Ljubinka Brashnarska of the UNHCR said in the phone from Skopje, Macedonia’s capital. “People seeking asylum need to be screened on individual merit, not on the basis of their nationality.”

Even for those who do manage to get through the border, the new restrictions have made life more difficult.

In the refugee camp on the Macedonian side, Ahmed, 44, said he had arrived with his wife and two children, ages 3 and 4, from Homs, Syria. He declined to give his last name for security reasons but said that after a harrowing journey from Turkey during which their boat had capsized, they arrived at the border with Macedonia the night before, only to find the crossing blocked by protesters. “We were there all night,” he said.

Still, he said he understood the situation for migrants who will have more difficulty than his family did in claiming asylum.

“The reception center on the Greek side is not ready for so many people,” he said. “And it is so cold. If they sleep there, they will die.”

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